in our original grant proposal we tested and verified the hypothesis that ethanol administered in ovo early in neuroembryogenesis or given in culture produced severe neuronotoxic effects, affecting differentially the cholinergic, GABAergic and catecholaminergic neuronal phenotypes. Furthermore, we demonstrated that growth factors, NGF, EGF, GHRH and SRIF given concomitantly with ethanol prevent or reverse these early neurotoxic effects. In this competing renewal application we will continue to use the chick embryo and neuron-enriched cultures either each system alone or in an in ovo/in vitro paradigm to further examine and identify more precisely cellular and molecular components involved in ethanol neuronotoxicity and the interaction of ethanol with growth factors. We propose the following studies: a) We will continue our current studies examining the effects of ethanol on growth factor binding sites and also the levels of mRNA encoding NGF, GHRH and SRIF, b) We will identify the survival of specific neuronal populations (cholinergic, GABAergic, catecholaminergic) after ethanol insult using the in ovo/in vitro paradigm and combination of immunocytochemistry and autoradiography. Similarly, we will test the effects of ethanol on cell migration using a combination of immunocytochemistry and autoradiography and we will examine neural cell adhesion by determining the level of NCAM expression during embryonic development. c) To test the hypothesis that ethanol shifts neuronal phenotypic expression we will examine in early embryos the levels of mRNA encoding TH, CHAT, and GAD proteins. d) To test the effects of ethanol on neuronal maturation we will examine in the in vivo/in vitro paradigm the activity df cAMP-dependent protein kinase as one transduction signal important for cell differentiation. With the recent advances in Fetal therapy, we hope that our studies will provide some basic clues of possible therapy and prevention of the Fetal Alcohol Syndrome.